This invention is generally directed to an apparatus for heating liquid-carrying conduits and is particularly directed to apparatus for heating conventional water pipes in homes and in industry, specifically for the purpose of thawing or preventing the freezing of water pipes in colder climates.
Prior art pipe heaters have been generally of the type which are attached to the exterior of water pipes and which include an electrical heating element for heating the pipe and the water inside. Although the heating units are usually provided with insulation, they use a great deal of energy for thawing frozen water pipes and for preventing the freezing of water pipes. Since the pipe itself must be heated, there is a considerable heat loss to the ambient air. In addition, prior art heaters are not always effective in extreme conditions of cold for either preventing the freezing of water pipes or thawing of frozen water pipes. After a pipe has been frozen, it usually requires a considerable amount of energy and time to unthaw the frozen area within the pipe before water can flow.
Other heating devices are known which are used in conjunction with special pipes provided with auxiliary channels for electrical heating elements that are separated from the main flow passage of the pipe. These heating units are used in special applications such as in heat-exchange systems and are not adaptable to the conventional water pipes that are found in homes and industry. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a pipe heater that is effective for preventing freezing of liquid-carrying pipes and the thawing of such pipes in even the most severe weather conditions.
Another object of this invention is the provision of a pipe heater which is efficient in the amount of energy that it uses for preventing the freezing of liquid-carrying pipes and thawing of frozen liquid in pipes.
A further object of the present invention is the provision of the pipe heater that is easily adaptable to existing pipes or fixtures.
It is another object of the instant invention to provide a pipe heater that can concentrate heat at the exact point of freeze for thawing frozen water in pipes.
A still further object of the instant invention is the provision of a pipe heater in which the amount of heat generated by the heater to the pipe can be controlled for different conditions.
It is a further object of the invention to provide a pipe heater which is simple in construction, which is easy to install, and which is capable of a long life of useful service with a minimum of maintenance.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.